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Defence Technology（防务技术） 2024年第2期32卷 412-429页

作者： Wenxue Chen yudong hu Changsheng Gao Ruoming An School of Astronautics Harbin Institute of TechnologyHarbin 150001China

This paper investigates interception missiles’trajectory tracking guidance problem under wind field and external disturbances in the boost ***,the velocity control in such trajectory tracking guidance systems of missiles is *** our contribution,the velocity control channel is designed to deal with the intractable velocity problem and improve tracking *** global prescribed performance function,which guarantees the tracking error within the set range and the global convergence of the tracking guidance system,is first proposed based on the traditional ***,a tracking guidance strategy is derived using the integral sliding mode control techniques to make the sliding manifold and tracking errors converge to zero and avoid ***,an improved switching control law is introduced into the designed tracking guidance algorithm to deal with the chattering problem.A back propagation neural network(BPNN)extended state observer(BPNNESO)is employed in the inner loop to identify *** obtained results indicate that the proposed tracking guidance approach achieves the trajectory tracking guidance objective without and with disturbances and outperforms the existing tracking guidance schemes with the lowest tracking errors,convergence times,and overshoots.

关键词： BP network neural Integral sliding mode control(ISMC) Missile defense Prescribed performance function(PPF) State observer Tracking guidance system

Trajectory tracking guidance of interceptor via prescribed performance integral sliding mode with neural network disturbance observer

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Defence Technology 2024年第2期

作者： Wenxue Chen yudong hu Changsheng Gao Ruoming An

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拦截高超声速滑翔飞行器:制导进展与展望

宇航学报 2024年第6期45卷 799-814页

作者：陈文雪胡玉东高长生荆武兴安若铭哈尔滨工业大学航天学院哈尔滨150001

聚焦于临近空间拦截制导关键技术,围绕中制导、中末制导交班及末制导等关键问题对临近空间拦截制导技术前景进行展望。首先对临近空间高超声速滑翔飞行器飞行特性进行仿真与分析,并给出防御系统在滑翔段拦截的优势所在;其次,围绕临近空... 详细信息

聚焦于临近空间拦截制导关键技术,围绕中制导、中末制导交班及末制导等关键问题对临近空间拦截制导技术前景进行展望。首先对临近空间高超声速滑翔飞行器飞行特性进行仿真与分析,并给出防御系统在滑翔段拦截的优势所在;其次,围绕临近空间拦截系统面对高超声速滑翔飞行器时存在的瓶颈进行探讨,并对中制导离线弹道生成与在线弹道生成、中末制导交班及末制导等关键技术相关研究进展进行梳理与总结;最后,结合当前研究进展、面临的挑战及未来临近空间拦截需求,研究分析临近空间拦截制导技术的发展趋势,为后续防御系统的发展提供参考。

关键词：临近空间拦截制导高超声速飞行器高动态机动目标防御技术

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高超声速飞行器改进阻力加速度剖面设计

现代防御技术 2024年第2期52卷 115-123页

作者：王哲浩李田闫海冬胡玉东高长生哈尔滨工业大学航天学院黑龙江哈尔滨150001 北京电子工程总体研究所北京100854

针对高超声速飞行器在滑翔段标称轨迹制导过程中的阻力加速度剖面设计问题,提出了一种改进的阻力加速度剖面设计方法。为增大飞行器滑翔段航程,改善飞行状态参数,设计了以能量倒数为自变量的二次函数形式剖面,通过改变剖面中点处阻力加... 详细信息

针对高超声速飞行器在滑翔段标称轨迹制导过程中的阻力加速度剖面设计问题,提出了一种改进的阻力加速度剖面设计方法。为增大飞行器滑翔段航程,改善飞行状态参数,设计了以能量倒数为自变量的二次函数形式剖面,通过改变剖面中点处阻力加速度值的方式对剖面形状进行调整,以满足高超声速飞行器各项约束。仿真结果表明,与传统二次函数阻力加速度剖面进行对比,该阻力加速度剖面能够增加最大滑翔距离,并改善飞行状态参数,能支持飞行器完成禁飞区绕飞任务。

关键词：高超声速飞行器标称轨迹制导滑翔段轨迹规划阻力加速度剖面过程约束

A novel adaptive lateral reentry guidance algorithm with complex distributed no-fly zones constraints

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Chinese Journal of Aeronautics 2022年第7期35卷 128-143页

作者： yudong hu Changsheng GAO Junlong LI Wuxing JING Wenxue CHEN School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Electronic System Engineering China Aerospace Science and Industry CorporationBeijing 100854China

Aimed at complex distributed no-fly zones avoidance problems,a novel adaptive lateral reentry guidance algorithm is ***,by introducing the improved attractive and repulsive potential fields,an improved artificial potential field method is *** with the proposed judgment criterion for whether a no-fly zone has been avoided,the proposed improved artificial potential field method effectively solves the reference heading angle determination problem under the constraints of complex distributed no-fly ***,based on the proposed no-fly zone’s threat quantitative evaluation method and the reference heading angle determined by the proposed improved artificial potential field method,the heading corridor is improved to increase its sensitivity to the threat changes of the no-fly ***,for satisfying the requirements of complex distributed no-fly zones avoidance,a novel guidance logic via improved heading corridor is proposed to update the reference heading corridor adaptively in real time according to the threat and constraint changes of the no-fly zones,and the bank reversal logic is employed to control the lateral *** simulation results for nominal and dispersed cases indicate that the proposed guidance algorithm has high robustness,stability,and applicability,and is feasible and effective to deal with the complex distributed no-fly zones avoidance problems.

关键词： Guidance strategy Heading corridor Hypersonic vehicles Improved artificial potential field Lateral reentry guidance Threat quantitative evaluation

南极磷虾活性肽对非酒精性脂肪肝病模型的保护作用研究

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浙江海洋大学学报（自然科学版） 2024年第1期43卷 11-19,32页

作者：骆鑫鑫胡渝东王斌赵玉勤浙江海洋大学食品与药学学院浙江舟山316022

以南极磷虾活性肽作为实验材料,采用油酸(OA)诱导人肝癌细胞(HepG2)建立体外非酒精性脂肪肝细胞模型,评价南极磷虾活性肽对体外非酒精性脂肪肝(NAFLD)的保护作用。利用NAFLD细胞模型筛选具有保护作用的活性肽,发现寡肽Val-Glu能够极显... 详细信息

以南极磷虾活性肽作为实验材料,采用油酸(OA)诱导人肝癌细胞(HepG2)建立体外非酒精性脂肪肝细胞模型,评价南极磷虾活性肽对体外非酒精性脂肪肝(NAFLD)的保护作用。利用NAFLD细胞模型筛选具有保护作用的活性肽,发现寡肽Val-Glu能够极显著降低细胞内TG含量(P<0.001)。之后对南极磷虾活性肽Val-Glu进行降脂活性评价,通过油红O染色实验观察到其能显著减轻HepG2细胞内脂质沉积;进一步对其进行抗氧化活性评价,结果表明Val-Glu能够显著抑制OA所引起的ROS生成增加,并且显著提高CAT、SOD和GSH-Px活力,降低脂质过氧化产物MDA含量。

关键词：南极磷虾活性肽非酒精性脂肪肝

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大质量比滚控式变质心飞行器动力学特性分析

宇航学报 2024年第2期45卷 250-261页

作者：孙佳慧胡玉东高长生荆武兴哈尔滨工业大学航天学院哈尔滨150001

针对大质量比滚控式变质心再入飞行器结构参数设计问题,建立了包含活动体偏转运动的完整飞行器姿态伺服动力学模型,进而对活动体参数设计对姿态动力学耦合特性的影响展开分析研究。首先根据Routh准则给出了飞行器的纵向静稳定区域,并讨... 详细信息

针对大质量比滚控式变质心再入飞行器结构参数设计问题,建立了包含活动体偏转运动的完整飞行器姿态伺服动力学模型,进而对活动体参数设计对姿态动力学耦合特性的影响展开分析研究。首先根据Routh准则给出了飞行器的纵向静稳定区域,并讨论了配平攻角与活动体配置参数间的关系。对飞行器系统的动力学耦合分析结果表明,活动体偏转在控制滚转姿态的同时会对偏航姿态产生影响,进而造成控制精度的下降,甚至导致不稳定的飞行状态。为了在飞行器结构参数的优化设计中提高飞行器的控制性能、最小化飞行器滚转机动对偏航通道的影响,采用多尺度法对活动体偏转与飞行器偏航姿态运动构成的耦合非线性动力学系统在不同构型参数下的稳态解析解进行幅频响应特性分析,并给出考虑滚转偏航耦合约束下的大质量比滚控式变质心飞行器构型设计方案。

关键词：变质心飞行器动力学耦合非线性振动结构参数设计

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定日镜场的输出热功率计算模型

台州学院学报 2024年第3期46卷 1-8,15页

作者：郑铛陆尹立胡宇冬李韶伟台州学院电子与信息工程学院浙江临海317000

基于全国大学生数学建模竞赛赛题的定日镜场分布数据,根据太阳视运动方法,建立太阳跟踪运动模型、阴影挡光效率理论模型、相邻定日镜遮挡选取模型与镜面反射光锥模型,得出了定日镜场的年平均光学效率、年平均输出热功率,以及单位面积的... 详细信息

基于全国大学生数学建模竞赛赛题的定日镜场分布数据,根据太阳视运动方法,建立太阳跟踪运动模型、阴影挡光效率理论模型、相邻定日镜遮挡选取模型与镜面反射光锥模型,得出了定日镜场的年平均光学效率、年平均输出热功率,以及单位面积的镜面年平均输出热功率,最后通过输出功率的拟合结果展现了模型的合理性。

关键词：定日镜遮挡阴影挡光效率太阳跟踪运动镜面反射光锥

Axial segregation characteristics and size-induced flow behavior of particles in a novel rotary drum with curved sidewalls

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Particuology 2024年第4期87卷 1-19页

作者： Qiuhua Miao Wenchang Zhu yudong Cao Peng huang Chaobin hu Minping Jia School of Mechanical Engineering Southeast UniversityNanjing211189China Jiangsu Key Laboratory for Elevator Inteligent Safety Changshu215500China

Particle mixing and segregation are common phenomena in rotary drums,which are challenging to be controlled and driven artificially in powder *** this work,the discrete element method(DEM)was applied to construct the novel rotary drum composed of different shaped curved *** varying the operation parameters of particle and sidewall shapes as well as the length-to-diameter(L/D)ratio of drums,the axial mixing and segregation processes of binary size-induced particles were *** results show that the axial flow velocity of the particle mixtures is noticeably weakened once the particle angularity increases,making the non-spherical particles to mix better in rotary drums compared to the spherical ***,in the short drums with size-induced spherical particles,the axial segregation characteristics are significantly enhanced by the convex sidewalls while suppressed by the concave ***,for size-induced non-spherical particles,the axial segregation structure can be present in rotary drums with plane and concave sidewalls while not in drums with convex ***,the axial segregation band structure of spherical particles eventually increases proportionally with the increased drum L/D *** contrast,the non-spherical particles cannot form obvious multi-proportional segregation bands.

关键词： Axial flow behaviors Size-induced particles Curved sidewalls Non-spherical particles Rotary drum

Efficient Ship:A Hybrid Deep Learning Framework for Ship Detection in the River

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工程与科学中的计算机建模(英文) 2024年第1期138卷 301-320页

作者： huafeng Chen Junxing Xue Hanyun Wen Yurong hu yudong Zhang School of Computer Engineering Jingchu University of TechnologyJingmen448000China School of Computer Science Yangtze UniversityJingzhou434023China School of Computing and Mathematic Sciences University of LeicesterLeicesterLE17RHUK

Optical image-based ship detection can ensure the safety of ships and promote the orderly management of ships in offshore *** deep learning researches on optical image-based ship detection mainly focus on improving one-stage detectors for real-time ship detection but sacrifices the accuracy of *** solve this problem,we present a hybrid ship detection framework which is named EfficientShip in this *** core parts of the EfficientShip are DLA-backboned object location(DBOL)and CascadeRCNN-guided object classification(CROC).The DBOL is responsible for finding potential ship objects,and the CROC is used to categorize the potential ship *** also design a pixel-spatial-level data augmentation(PSDA)to reduce the risk of detection model *** compare the proposed EfficientShip with state-of-the-art(SOTA)literature on a ship detection dataset called *** show our ship detection framework achieves a result of 99.63%(mAP)at 45 fps,which is much better than 8 SOTA approaches on detection accuracy and can also meet the requirements of real-time application scenarios.

关键词： Ship detection deep learning data augmentation object location object classification